Click default QPushButton when Enter SpinBox - c++

Question

I need to raise the click signal of my QPushButton when I press Enter on QSpinBox (actually on every input box), but even if my button is the default button, the following code doesn't work.
#include <QApplication>
#include <QHBoxLayout>
#include <QPushButton>
#include <QSpinBox>
#include <QMessageBox>
int main(int argc, char* argv[])
{
QApplication app(argc, argv);
QWidget* window = new QWidget();
QSpinBox* spinbox = new QSpinBox();
QPushButton* button = new QPushButton("Ok");
button->setDefault(true);
QObject::connect(button, &QPushButton::clicked, []()
{
QMessageBox::question(nullptr, "Test", "Quit?", QMessageBox::Yes|QMessageBox::No);
});
QHBoxLayout* layout = new QHBoxLayout();
layout->addWidget(spinbox);
layout->addWidget(button);
window->setLayout(layout);
window->show();
return app.exec();
}
How can I fix it?

Answer 1

You can see in the Qt documentation about QPushButton :
The default button behavior is provided only in dialogs
You are using a QWidget and expect the default button behavior to work. Just use a QDialog instead of QWidget :
QDialog * window = new QDialog();
...

Answer 2

you can use Event
The QObject::installEventFilter() function enables this by setting up
an event filter, causing a nominated filter object to receive the
events for a target object in its QObject::eventFilter() function. An
event filter gets to process events before the target object does,
allowing it to inspect and discard the events as required.
void QObject::installEventFilter ( QObject * filterObj )
Installs an event filter filterObj on this object. For example:
monitoredObj->installEventFilter(filterObj);
An event filter is an object that receives all events that are sent to
this object. The filter can either stop the event or forward it to
this object. The event filter filterObj receives events via its
eventFilter() function. The eventFilter() function must return true if
the event should be filtered, (i.e. stopped); otherwise it must return
false.